"Psycho-analysis has taught us that a boy's earliest choice of objects for his love is incestuous and that those objects are forbidden ones - his mother and his sister. We have learnt, too, the manner in which, as he grows up, he liberates himself from this incestuous attraction. A neurotic, on the other hand, invariably exhibits some degree of psychical infantilism. He has either failed to get free from the psychosexual conditions that prevailed in his childhood or he has returned to them - two possibilities which may be summed up as developmental inhibition and regression."